Cast hinge

ABSTRACT

A cast hinged article and the method and apparatus for simultaneously casting both parts of the article. A first part of the article is formed with inner projections, and a second part of the article is formed thereover to enclose the projections to provide a hinged pivot. A staking unit which includes a punch then distorts the material in the first part adjacent the projections so that the pivot will be freely movable.

United States Patent 11 1 Hannes i 1 CAST HINGE [75] lnventor: Ka rlHannes, White Plains, NY. [56] References cued 73 A C Cl I N Y k UNITEDSTATES PATENTS sslgnee' 6W 3.497908 3/1970 Zamarra 1. 16.4 1

[ Notice: The portion of the term of this Primary Examiner-Paul- R.Gilliam patent subsequent to July 30, 1990, Assistant ExaminerDo'ris L.Troutman has been disclaimed. 221 Filed: May 30, 1973 [57] 1 ABSTRACT Acast hmged art1cle and the method and apparatus PP 365,269 forsimultaneously casting both parts of the article. A

Re'ated s Application Data first part of the article is formed withinner projec- [63] bummumiomim a" of Ser No 187 427 0c 7 tions, and asecond part of the article is formed there- 1971 Pat NO 3p742 555 1 overto enclose the projections to provide a hinged 1 f 1 1 pivot. A stakingunit which includes a punch then dis- [52] CL 16/171 torts the materialin the first part adjacent the projec- [51] Int. Cl 1 1/06 tions so thatthe pivot will be freely movable [58] Field of Search 16/171 8 Claims,18 Drawing Figures ll 1 I 1 24 1' l 1' 361 38" :j. "#38 3O I ,1! 50 lil 1. 26 1 40 PAIENTEU sac x 11974 SHEET '2 OF 4 PATENTEL 35B 1 3,854,166

SHEET l 0F 4 f 1 CAST HINGE This application is a continuation-in-partof my copending application Serial No. 187,427, filed October 7, 1971now Patent No. 3,742,555.

BROAD STATEMENT OF INVENTION The present invention relates to a casthinged article made by casting the parts of the article simultaneouslyto be pivotal on each other with the hinged pivot being treated to befreely movable.

DESCRIPTION OF THE PRIOR ART It is known in the prior art to eastpivotal or hinged I elements to form an integral unit. An example ofsuch casting is shown in US Pat. No. 2,819,494 issued on Jan. 14, 1958to Louis H. Morin. In such prior art casting a pivot was provided thatwould allow one element to be rotated with respect to the other.However, in this type .of casting where a second element is formed overa prior formed element, a degree of binding is present so that therelative movement of the two elements is not freely rotatable. In theaforementioned patent this is not necessarily a disadvantage since abelt buckle is the product involved. However, for other elements,

- such as a hinge; where this type of casting process is utilized,movement of the pivot free of binding is desired.

DESCRIPTION OF THE INVENTION with the first element being distorted sothat the pivot is freely movable.

A further provision of the-subject invention is the provision ofconnected elements forming a hinge wherein a first one of the elementsis formed withprosion of the depression means provides a freely movablepivot area.

The nature of the present invention will become more clearly apparentand better understood from the jections and the other element is formedthereover to provide a pivot for thehinge, and depression means areformed in the first element to spread the projections to free the pivot.

A still further provision of the present invention is to I provide anarticulated element formed between movable dies wherein one element iscast over another element to form a hinged area, and the connected elements are positioned between staking means that in- In a preferredembodiment of the invention an article is provided comprisingarticulated elements of which following description and accompanyingdrawings, in which:

FIG. 1 is an elevational view of the one side of the hinged article ofthe present invention showing the decorative formation thereon;

FIG. 2 is an elevational view of the other side of the hinged productshowing the flat-sided formation and depressions formed therein;

FIG. 3 is a side view of the hinged product shown in FIGS. 1 and 2;

FIG. 4 illustrates the installation of the article shown in FIGS. 1-3;

FIG.'5 is a view similar to FIG. 2 showing a lower element of the formedarticle in enlarged form;

FIG. 6 is a perspective view of an upper element of the formed article;

FIG. 7 is a diagrammatic view illustrating the apparatus and method forforming the article shown in FIGS. 1-3;

FIG. 8 is an exploded perspective view of one opposed means thatprovides the distortion of the element shown in FIG. 5;

FIG. 9 is an exploded perspective view of another opposed means thatprovides the distortion of the lower element shown in FIG. 5;

FIG. 10 is a view of the opposed means shown in FIGS. 8 and 9 inassembled condition prior to contacting the formed article foradistortion step;

FIG. 11 is an elevational view of punch means located in the opposedmeans;

FIG. 12 is an end view of the punch means shown in FIG. 11; g

FIG. 13 is a plan view of shown in FIG. 11;

FIG. 14 is a perspective view of part of the end of the punch meansshowing raised areas thereon;

FIG. 15 is an elevational view of a modification of the embodiment ofFIG. 2;

FIG. 16 is an elevational view of a modification of the embodiment ofFIG. 5;

FIg. 17 is an elevational view of a further modificapart of the punchmeans tion of the embodiment of FIG. 5; and

. 22 as shown in FIG. 1 and a rear flat side 24 as shown in FIG. 2. Thearticle illustrated is a decorative hinge although it is to beunderstood that the invention is not the first element isformed withprojections around which the second element has been formed to provide apivotal joint. The first element includes depression means formedtherein which distort and spread the material in the area of theprojections. In the embodiment illustrated a pair of spaced paralleldepressions are formed in the first element to provide for the movementof the projections which releases any binding be tween the first andsecond elements. The article can be made in the form of a decorativehinge, and the incluto be so limited since the invention is consideredto encompass any articulated element to be provided with a freelymovable pivot. Front surface 27 of the hinge in cludes a decorativesurface such as the illustrated embodiment of a fleur de lis patternwhich includes part of the pattern formed as raised surfaces to providethe decorative effect which can be enhanced by polishing and finishing.Article20 includes a first cast hinge element or lower section 26 and asecond cast hinge element or upper section 28. Element'26 is connectedtions-similar to the projections 36.

with element 28 by a pivot or hinge means 30. As mentioned above, frontsurface 22 includes raised areas surfaces 36 formed on the facingsurfaces of the extensions, as shown in FIG. 5, the projectionsextending inwardly toward each other in opposed relation. Eachprojection 36 is tapered (e.g., with frustoconical surfaces) so that itscross-section is smallest at its remote end. Upper element 24 is formedwith an extension depending from the base or body of this member, theextension having a-pair of aligned recesses or enclosure areas 38 (e.g.,with frusto-conicalsurfaces) on opposite edges as shown in FIG. 6,formed to fit respectively around the projections 36 to complete thehinge. The frusto-conical surfaces thus form bearing surfaces. FIG. 3shows the upper element 28 in solid lines where it is aligned with lowerelement 26 so that the entire hinged 44 while the lower or smallerelement 26 would be attached to the back side 48 of the box 44. It isimportant that the pivot 30 provide a freely movable relationship 1between the elements so that top lid 46 does not bind and is easlilyrotated foropening and closing, The novel decorative hinge of theinvention could also be-used on louvered doors or cabinets or similarstructures, andit is understood that the size and thickness of the hingecould be varied depending upon the strength required and the size of thestructure involved. Similarly, the

decoration could be changed and other designs utilized article 20 isflat while the dotted line position of element 28 in FIG. 3 illustratesa pivoted position around hinge means 30. As will be apparent in thefollowing disclosure,'each of the elements 24 and26 are cast elements,with one of these elements being initially-cast and forming a portion ofthe mold surface for the second element, i.e., in the region of thebearing surfaces- In this manner of forming the article, a tight fitcan,occur between the elements on their adjoining surfaces, which mayinterfere with free pivotal movement at the pivot joints. The article,formed in this manner, thus does not require any further assembly of theelements. The projections 36 extend into the enclosure areas 38 asufficient distance that, this being a cast article, the elements cannotbe separated without destruction of the article. Similarly, it'isapparent that separate first and second elements cannot be assembledwithout destruction of the article. It is further to be pointed outthat, while it is preferred that the projections 36 and enclosure areas38 be provided on the respective elements 26 and 28 as illustrated inFIGS. 5 and 6, it is apparent that the respective positions of theprojections 36 and enclosure areas 38 may be reversed. In other words,the element 26 may be provided with enclosure areas, and the element 28may be provided with projec- A pair of spaced holes 40 are formed inlower element 26. The particular spacing, number and location of holes40 is not a critical feature of the invention as long as these holes aresufficiently spaced apart to re ceive screws, nails or other fasteningmeans for holding the article in place when installed. Similarly, a pairof spaced holes 42 are. provided in the upper element 28 for the samepurpose of receiving similar fastening means for installation. Althoughfour holes are illustrated, it is to be understood that more orless thanfour holes could be utilized for fastening an article such as thedecorative hinge illustrated to the structure where it is utilized.

FIG. 4 illustrates a typical installation of article 20 as a hinge for acontainer such as ajewelry box 44. A typical decorative hinge for thispurpose would be approximately l-2 inches in length and'the upper orlarger element 28 would be attached to the top lid 46 of the box as longas the freely movable pivot feature is present.

The freely movable feature of the pivot is provided by a compressedregion or depression means 50 formed in the first element 26. As mostclearly seen in FIG. 5, depression means 50 comprises a pair of spaced,parallel, elongated depressions 52'and 54 that extend longitudinally inelement 26 with each depression respectively aligned generally with aprojection 36 and preferably normal to the pivotalaxis, as illustrated.Depressions 52 and 54 are formed by a punch orsimilar device beingforced into element 26 to thereby spread the material in the area aroundeach projection 36. Accordingly, it will be appreciated from aconsideration of FIG. 5 that depressions 52 and 54 provide a distortionof the material around each of projections 36 so that they will pivotfreely within enclosures 38 of pivot hinge 30. In other words thematerial of the element is distorted in a direction'tending to separatethe extensions on member 26 from their cast positions, and hence toloosen the pivot joint.

While the hinge member 26 as illustrated in FIGS. 2 and 5 is shown asbeing provided with two parallel depression means 50, it will beapparent that the number, type and size of such depression means can bevaried depending, for example, on the form of the hinge itself and thematerial of which the hinge is made. Thus, in

.the dimensions of the article are such that it would be more difficultto provide two such depressions aligned as shown in FIGS. 2 and 5.Furthermore, it is apparent that more than two parallel depression meansmay be provided if desired, for example, with larger size hinges, andalso when the metallurgical characteristics or shape of the hingestructure limit the spreading that can be effected in a practical manneronly by two such depressions.

In addition, while the depressions illustrated in FIGS. 2 and 5 areshown as being spaced from the pe= rimeter of the hinge member 26, thisdepiction of the depression means is not intended to be limiting, sinceif desired, the depression means may extend to the pe rimeter of thehinge member 26 as shown in FIG. 15,

in exaggerated form, and thus in an actual structure the depression maybe only barely visible. For example, a large punch may be employed toeffect the general spreading of the material in the central portion ofthe hinge member coextensive with the region aligned with theprojections 36 and the region therebetween. A die member for effectingsuch'spreading may, if desired, be smoothly rounded whereby-a generalconcavity is produced in the hinge member 26 instead of the discreetlinear depression means as illustrated in FIGS. 2 and 5,

The casting apparatus of the invention is shown scheulated relationtherewith is shown in aforementioned U.S. Pat. No. 2,819,494. This isprovided by having die 60 and a mating die relatively movable toward andaway from each other to allow the vertical movement of the elementsbeing formed in sequential steps. During the formation heated materialfrom an injection nozzle (not shown) flows into a gate 62 in thedirection shown by arrow A. The heated material flows around a transfercore pin 64 to form a ring-like upper gate portion 66 and a lower gateportion 68. It is to be appreciated that this is a known feature to flowthe heated metal into molds formed in mating diesto simultaneously formupper and lower elements in articulated form. In the upper part of thedie60 the gate 66isseen to include paths 70 and 72 arranged todirectseparate flows obliquely with respect to each other to completely formone lower element 26. Simultaneously with the flow into gate 66 there isalso a flow intolower gate 68 to form the upper or second element 28 inarticulated condition with a previously formed lower element thathasbeen transposeddownwardly. This is provided by flow paths 74 and 76located obliquely with respect to each other to disperse the heatedmaterial throughout the mold in forming element 28. The articulatedformation is correlated with openingand closing of the dies so that justprior tothe material flowing step, the movable dies had been separatedand the transfer core pin 64 had moved the previously formedelement 26down to the lower position where it is shown in'FlG. 7 as element 26.Accordingly, it isto be understood that each time the heated materialflows into gate 62 and through portions 66 and 68 into the molds, afirst or lower element 26is formedin theupper position and The stakingstep is an important feature of the present invention, and the stakinglocation is located directly below movable die so that the articulatedelements 26, 28 in solid form that form a completed hinged article aremoved downwardly thereto by the intermittent vertical movement of thetransfer core pin 64. The staking step is for the purpose of treatingthe first or lower element now indicated as element 26" so that itsprojections 36 will be freed from binding within the enclosures 38located in element 28'. It is in this staking location that element 26"is subjected to a staking or punching deformation of the material in thecentral area of the element toform the depression means 50. The type ofmaterial that is supplied in the heated form to be solidified isa zincalloy which is known as Zamak No. 3. However, the invention is not to becon sidered to" be limited to a zinc alloy. as any material of similarnature can be used which is capable of being melted and injected in theflowable form to be solidified in the mating molds.

The staking or punch operationwill now be described, and it is to benoted that the staking location is just below and closely adjacent tothe forming molds so that the solidified elements 26" and 28' are stillin a heated condition allowing the depressions and spreading of themetal to be easily performed.

FIGS. 8 and 9 illustrate the elements that form the staking unit whicharepositioned in opposed relation as shown in FIG. 10'. The hingedarticle shown as elements 26 and 28' that is to be staked or punched ismoved intothe lower position as shown in FIG. 10 between opposed units80 and 82 that are movable toward each clud'es the decorativeornamentation. For this purpose opposed unit 80' includes an outer coveror housing 84 which includes horizontally spaced parallel bores 86 and88 for including therein stiff compression springs 90 and 92.respectively. The right-hand surface of a completed hinged article isformed in the lower posi- 1 tion by element 28 being cast with itslowerenclosure portions 38 molded around solidified projections 36-.

It will also be seen in FIG. 7 that when first element 26representingthe lower half of the hinged article has moved downward towhere it appears as a solidified element 26, then gate'elements 62, 66and-"68appear as solidifiedgate elements 62 66 and-68. t

It will further be appreciated from an examination of FIG. 7 that whenelement 26 moves-to its first-lower position wherelit appears assolidified element 26" that an element 28 that had beenpreviously formedthen 'moves to a further lower or staking position where it appears assolidified element- 28 where it is seen to be in articulated connectionwith a solidified first-element 26' that had been previously. formedan'dmoved downwardly to the staking position.

housing 80 that includesthe bore openings 86 and 88 is formed with anotched or depressed area 94 that is oblong in shape as shown in FIG.7'to include the open-' ings of bores 86 and 88 and be substantially ofthe same size as the hinged article 20. Within the notched area 94* isfitted one end 96 of a trim punch 100 which includes a raised portion10-2 on its other end that issubstantially of the same size and shape asthe front surface of hinged element 20. From a consideration of FIG. 8it willbe seen that trim punch 100 includes the oblong shaped endportion 96 that fits within slot 94, a section 104 that extends fromend- 96- and has a similar but slightly smaller oblong shape with itstop surface aligned with the top surface of end portion 96', the

raised portion 102 which includes upper and lower parts 106 and 108 ofgenerally the same configuration as the entire front surface 22, and arecessed groove around so that part of a backsurface of cover 112 ispressed against a-flat-surface l 03 'whichis the frontsurface of end 96that contacts extended portion 104. Cover 112 and housing 84 have agenerally rectangular shape although this is not an essential feature ofthe invention. Cover 112 further includes a depressed area i 116 in theform of three connected legs shaped to receive the solidified gates 62',66 and 68 when they have been moved into the staking location.Accordingly, depression 116 has generally the same shape as the gateportions shown in FIG. 7 and the trimming of the gate portions from thehinged product 26", 28 is provided at this position.

Opposed means 82 includes housing 120 which is shaped similarly tohousing 84 and includes horizontally spaced parallel bores 122 and 124terminating in openings 126 and .128 within which stiff compressionsprings 130 and 132 are respectively located. On the surface of housinglfacing hinged product 26", 28' a recessed area 134 is formed which isoblong in shape and substantially'of the same size as the hinged product26", 28 and further includes the openings 126 and 128 as shown in FIG.9.

A second contacting part of trim pad 140 is provided which includes anend 142 of such oblong size that fits within recessed area 134. Trim pad140 is seen in FIG. 9 to include the oblong end section 142, and araised portion 144 is-formed thereon in a shape of generally the samesize and corresponding to the shape of the hinged product. The surfaceof portion 144 is positioned to contact the back surface of the hingedproduct and is generally flat to correspond with surface 24 as shown inFIG. 2. It will be noticed in FIG. 9 that the top surface of raised area144 is generally in line with the top surface of end 142, but end 142extends further .downwardly than area 144 in order to receive a cover ona flat surface 146 that is formed on a front side of end 1'42.v

- A cover 150 fits around trim pad 140 and against the inner surface ofhousing 120. Cover 150 includes a centrally located cut-out portion 152which is generally of the same shape as raised portion 144 so as to fitthereabout with the rear surface of cover 150 abutting flat surface 146as well as the inner surface 129 of housing 120. It will be seen in FIG.9 that cover 150 includes a cut-out portion 152 that extends into theupper surface of cover 150 to form a notched opening 156 to accommodatethe upper tip of hinged product 26", 28' in the position shown in FIG.9. Cover 150 also includes a depression 154 that is in the general shapeof the gate portions 62', 66 and 68. It is to be understood thatdepression 154 corresponds in opposing location and shape withdepression 116 to enclose the gate portions to provide for trimming andremoval thereof from the cast product.

It will be noted in FIGS. 9 and 10 that an opening 146 is provided inthe lower part of trim pad 140. A corresponding opening 158 is formed inthe rear of housing 120 so that a punch 160 can be slidably positionedtherein as shown in FIG. 10. It will be noted that punch 160 as well ashousing 120 and cover 150 have a generally rectangular shape, but thisis not a critical feature of the invention.

The function of punch 160 is to provide the staking operation whereinthe punch is acted upon at one end by means not shown which would passopening 158. The other end of punch 160 is thereby driven into the backof element26" to form. depressions 50 as described hereinbefore tospread the material and free the pivot. I

As seen in FIGS. 11-14 punch 160 is an elongated member with a generallysquare shape in cross section and includes chamfered edges 162 along itselongated edges. Punch 160.has an end 164 that is forced into the lowerelement of product 20. End 164 includes a pair of parallel raised areas166, and the punch and raised areas are formed of a materialsufficiently hard,- such as hardened tool steel, to press into the lowerelement 26" without deformation of the punch or raised areas. Asmentioned previously, the forcing of raised areas 166 into the lowerelement is facilitated since the product is still in the heatedcondition from the molding operation.

} Each raised area 166 has a particular configuration to facilitateentry and spreading of the material in order to free projections 36 fromenclosures 38. As most clearly seen in FIG. 14, each raised area 166includes an inner surface 168 projecting perpendicularly from the end164 of punch 160. Surface 168 extends on the order of 0.02 inches andthen is curved outwardly to form a curved surface 170 terminatingadjacent the respective chamfered edges and outer side of the punch.

The radius of the curved surface 170 is approximately 0.05 inchesmeasured from the outer edge of surface 168. It is an important featureof the invention to have curved surface 170 so that the penetration byraised areas 166 is first achieved along the outer edges 172, and thecontinued penetrating movement of the punch causes the material tospread outwardly because of the curved surface 170. The spacing of eachraised area 166 from each other is not a cirtical feature of theinvention as long as such spacing is in general alignment with theparticular location of the projections 36 so that the spreading of thealloy material is effective to move the projections into freely pivotalmovement with respect to enclosures 38. The actual spread or deformationof the material is about 7- 10 mils.

When the contact is made by opposed units '80 and 82 being pressedagainst the opposite side of hinged product 26", 28, punch 160 is drivenby the means not shown so that the raised areas 166 are forced into theback of lower element 26" to spread the material and provide the freepivotal motion. With this driving or staking step the springs 90, 92 and130, 132 provide a resilient support for the contacting parts and sothat a small amount of movement of "give" is permitted with respect toparts 100' and 140.

While the punch as illustrated in FIGS. ll-l4 is provided with tworaised areas 166 for spreading of the material in the hinge member, itwill be apparent that the punch may be provided with any number ofprojections depending upon the design of the hinge as above discussed.For example, when a single depression means is to be provided in thehinge member 26 as shown in FIG. 16, the punch will of course beprovided with a single projection, the sides of the projection beingshaped to effect the spreadingof the material in opposite directions,for example with curved surfaces I as illustrated in the outward sidesof the projections 166 in FIGS. 13 and 14. Similarly, when the spreadingof the projections 36 is to be effected by a larger area punch, toprovide the modification of FIGS. 17 and 18, the punch may have agenerally convex cross section to effect the general movement of thematerial from the center of the hinge member without forming thediscreet depression mark. The invention thus contemplates thecompression or punching of the central portion of the hinge memberwhereby material in the central portion or bridge area of the hingemember 26 is outwardly forced to effect the spreading of the projections36. It will further be apparent that the invention also encompassesspreading of the hinge member in the event that the hinge is formed withthe projections and enclosure areas in opposite relative positions ascompared with the hinge shown in FIGS. 2, and 6, i.e., with outwardlyextending projections on the hinge member 28 replacing the enclosureareas 38 and adapted to mate with enclosure areas on the hinge member 26replacing the projections 36.

From the above description it is clear that the present inventiondiscloses a novel articulated or hinged element wherein one element hasdepressions formed therein to spread the projections forming the hingefor free movement.

Another feature of the present invention is the provision of the castingapparatus for the articulated elements which includes staking or punchmeans that provides opposed units for contacting the articulatedelements so that the punch can cause the distortion or spreading of thematerial for the freeing of the pivot.

A further feature of the present invention is the method of casting thearticle whereby the articulated elements are moved into the stakingposition, and the punch means are driven into one of the elements tospread the material for the loosening and freemovement of the pivot.

It will be understood that various modifications and changes may be madeby those skilled in the art in the particular features of the article,apparatus and method which has been described above for illustrativepurposes without departing'from the scope of the invention as defined bythe following claims.

What is claimed is: e i

1. An article having a first element, first and second parallelextensions depending from an edge of said first element, first andsecond bearing means on said first and second extensions, the bearingmeans being aligned and directed toward each other,

a second cast element, extensionmeans depending from an edge of saidsecond cast element, third and fourth aligned bearing means on saidextension means and being directed away from each other, and engagingsaid first and second bearing means respectively to form an articulatedjoint,

the respective bearing means being sufficiently overlapped to preventnon-destructive assembly and disassembly of said first and secondelements,

saidfirst element having a compressed region between said first andsecond extensions in which the material of the first element isdistorted'in a direction tending to separate said first and secondextensions. 2. A hinge having first and second hinge elements, saidfirst element having a first base with a flat side,

a pair of first parallel spaced apart extensions depending from an edgeof said base, and aligned first bearing surfaces on said extensions andintegral therewith, the first bearing surfaces being on facin sides ofsaid first extensions,

said second element having a second base with a second extensiondepending from an edge thereof, and a pair of aligned second bearingsurfaces on opposite edges of said second extension and cast integrallytherewith,

said elements being assembled with each first bearing surface engaging asecond bearing surface, to form pivot joints, one bearing surface ateach joint being in the form of a recess and the other bearing surfaceat each respective joint being in the form of a bearing projectionextending into the respective recess a distance sufficient to preventnondestructive assembly and disassembly of the first and secondelements,

said first element further having a punch formed depression in said flatside between said first extensions which distorts the shape of saidfirst element,

said depression being positioned to relatively displace said tirstbearing surfaces in opposite direc- I tions, whereby the pivot jointsare loosened.

3. The hinge of claim 2 wherein said bearing surfaces arefrusto-conical.

4. The hinge of claim 2 wherein said punch, formed depression is a slotin said flat side extending in a direction normal to the pivot axis ofsaid hinge elements.

5. The hinge of claim 2 wherein said punch formed depression comprises apair of parallel slots extending in said flat side in a direction normalto said pivot axis, said slots being generally aligned with separatepivot joints.

6. The hinge of claim 2 wherein said punch formed depression comprises asingle depression extending substantially the distance between saidfirst projections in said first base.

7. The hinge of claim 6 wherein said depression is formed substantiallywithout discreet edges on the adjoining undistorted surfaces of saidflat side.

extensions.

1. An article having a first element, first and second parallelextensions depending from an edge of said first element, first andsecond bearing means on said first and second extensions, the bearingmeans being aligned and directed toward each other, a second castelement, extension means depending from an edge of said second castelement, third and fourth aligned bearing means on said extension meansand being directed away from each other, and engaging said first andsecond bearing means respectively to form an articulated joint, therespective bearing means being sufficiently overlapped to preventnon-destructive assembly and disassembly of said first and secondelements, said first element having a compressed region between saidfirst and second extensions in which the material of the first elementis distorted in a direction tending to separate said first and secondextensions.
 2. A hinge having first and second hinge elements, saidfirst element having a first base with a flat side, a pair of firstparallel spaced apart extensions depending from an edge of said base,and aligned first bearing surfaces on said extensions and integraltherewith, the first bearing surfaces being on facing sides of saidfirst extensions, said second element having a second base with a secondextension depending from an edge thereof, and a pair of aligned secondbearing surfaces on opposite edges of said second extension and castintegrally therewith, said elements being assembled with each firstbearing surface engaging a second bearing surface, to form pivot joints,one bearing surface at each joint being in the form of a recess and theother bearing surface at each respective joint being in the form of abearing projection extending into the respective recess a distancesufficient to prevent non-destructive assembly and disassembly of thefirst and second elements, said first element further having a punchformed depression in said flat side between said first extensions whichdistorts the shape of said first element, said depression beingpositioned to relatively displace said first bearing surfaces inopposite directions, whereby the pivot joints are loosened.
 3. The hingeof claim 2 wherein said bearing surfaces are frusto-conical.
 4. Thehinge of claim 2 wherein said punch formed depression is a slot in saidflat side extending in a direction normal to the pivot axis of saidhinge elements.
 5. The hinge of claim 2 wherein said punch formeddepression comprises a pair of parallel slots extending in said flatside in a direction normal to said pivot axis, said slots beinggenerally aligned with separate pivot joints.
 6. The hinge of claim 2wherein said punch formed depression comprises a single depressionextending substantially the distance between said first projections insaid first base.
 7. The hinge of claim 6 wherein said depression isformed substantially without discreet edges on the adjoining undistortedsurfaces of said flat side.
 8. The hinge of claim 6 wherein saiddepression extends to the edge of said first element between said firstextensions.